Activity meter PNT 3000

direct measurement of soil salinity

The Activity Meter PNT 3000 (Plant Nutrition Tester) measures the salinity of the soil or substrate, taking into consideration the relevant soil properties, like soil moisture, temperature and soil compaction.

The salinity is determined by the concentration of total dissolved salts. In water and/or suspensions, those salts are completely free and mobile and can be measured by means of a conductivity (EC) measurement. In soils, peat or other greenhouse media, however, the salts are not totally dissolved.

Their mobility depend on

• soil moisture
  
  
• soil compaction
  
  
• soil temperature

These factors determine the quantity of salts being "active" and available to the plants. As the plant nutrients, like nitrate, potassium, etc., are salt ions, the measurement of "active" salt ions gives an immediate information about the plant nutrition status.

The measuring principle of "activity" has been developped by Prof. Dr. Tepe, a former director of the Research Institute for Soil Science and Plant Nutrition Geisenheim, Germany. Since then this method has been applied as an easy, fast and reliable control of plant nutrition.

The PNT 3000 means the latest step of development of all activity meters. The production is based on modern SMD-technology which is applied for all meters of the "3000-line". This technology is considered to be much more reliable and temperature-resistant than the conventional wire technology. The rugged housing is waterproof and field-ready - the operation of the instrument convenient and simple. Only one button makes the full operation of the PNT 3000 possible. The instrument is checked and calibrated before leaving the factory - a re-calibration is not necessary.

The probes are made out of stainless steel and are available in three different length. A special maintenance or storage of the equipment is not required.

The PNT 3000 is supplied with guidelines (optimal values) for all plants and an easy understandable short operation manual based on pictograms.

To be supplied as

• basic unit PNT 3000 in carton, with stainless steel probe 25-cm and /or 50 cm
  
  
• basic unit PNT 3000 and 25-cm stainless steel probe in modern, high-quality aluminium transport and storage case

Application of the portable PNT 3000 to measure soil salinity on the spot - without conducting soil sampling and soil preparation:

• pot plant production in all terms of plant status, propagation, maturity, etc.
  
  
• nurseries: container plants, particularly if long-term-fertilisers are applied
  
  
• landscape: golf course greens, sporting grounds, etc.
  
  
• peat production for immediate check during production process
  
  
• compost plants: to avoid excess of salt concentration in compost soils
  
  
• communities, local governments: determination of soils charged with chloride after winter period
  
  
• consultants, advisors, salesman, etc.
  
  
• universities, schools, horti-/agricultural educational

Technical data

Housing: waterproof, rugged
Dimensions: 180 x 85 x 50 mm
Power supply: 9-Volt battery, > 4000 measurements
Connector: 5 pin plug
Weight: 280 g

Activity measurement

Measuring range: 0 - 10 activity in g/l
Resolution: 0,01 activity in g/l
Calibration: re-calibration not needed
Probe: stainless steel with special 2-pol-sensor
Probe length: 250, 500 and 750 mm